1. Field of the Inventive Subject Matter
The present inventive subject matter relates to novel methods for treating prostate cancer, comprising administration of a composition comprising therapeutically effective amounts of supercritical extracts of rosemary, turmeric, oregano and ginger; and therapeutically effective amounts of hydroalcoholic extracts of holy basil, ginger, turmeric, Scutellaria baicalensis, rosemary, green tea, huzhang, Chinese goldthread, and barberry.
2. Background
Prostate Cancer. Prostate cancer is the third most common cause of death from cancer in men of all ages and is the most common cause of death from cancer in men over 75 years old. Prostate cancer is rarely found in men younger than 40. Men at higher risk include black men older than 60, farmers, tire workers, painters, and men exposed to cadmium. The lowest incidence occurs in Japanese men and vegetarians. The cause of prostate cancer is unknown, although some studies have shown a relationship between high dietary fat intake or increased testosterone levels.
Prostate cancer is a serious and often life-threatening condition. Prostate cancer, which is characterized by rapidly-proliferating cell growth, continues to be the subject of worldwide research efforts directed toward the identification of therapeutic agents which are effective in the treatment thereof. Effective therapeutic agents prolong the survivability of the patient, inhibit the rapidly-proliferating cell growth associated with the disease, or effect a regression of the disease. Research in this area is primarily focused on identifying agents which are therapeutically effective in humans and other mammals.
With prostate cancer, as with all solid tumors, it is the metastatic encroachment of the tumor on other vital function that causes the demise of the patient. Approximately 10% of patients are diagnosed initially with metastatic disease. Ultimately, 30–40% of patients with this cancer will develop metastatic disease. Once metastasis occurs, the cancer follows a relentless progression unless interrupted by effective treatment. Prostate cancers are classified based on their aggressiveness and how different they are from the surrounding prostate tissue. There are several different ways to classify tumors; one of the more common is the Whitmore-Jewett system, in which tumors are rated as follows:                A: tumor is unable to be felt on physical examination, and is usually detected by accident after prostate surgery done for other reasons.        B: tumor is confined to the prostate and usually detected by physical examination or PSA testing.        C: extension of tumor beyond the prostate capsule without spread to lymph nodes.        D: cancer has metastasized to regional lymph nodes or other parts of the body, such as the bone and lungs for example.        
With the advent of Prostate Specific Antigen (hereinafter “PSA”) testing, most prostate cancers are now found before they cause symptoms. The symptoms listed below are possible indicators of prostate cancer: urinary hesitancy, urinary dribbling, urinary retention, pain with urination, pain with ejaculation, lower back pain, pain with bowel movement, excessive urination at night, incontinence, bone pain or tenderness, hematuria, abdominal pain, anemia, weight loss, and lethargy.
The appropriate treatment of prostate cancer is often controversial. Treatment options vary based on the stage of the tumor. In the early stages, surgical removal of the prostate and radiation therapy may be used to eradicate the tumor. Metastatic cancer of the prostate may be treated by hormonal manipulation, reducing the levels of testosterone by drugs or removal of the testes, or by chemotherapy.
Surgical removal of the prostate has several possible complications, including impotence and urinary incontinence. Removal of the testes alters hormone production and may be recommended for metastatic cancer, and has possible complications including loss of testosterone production, leading to problems with sexual function, osteoporosis, and loss of muscle mass. Radiation therapy has possible complications including loss of appetite, fatigue, skin reactions such as redness and irritation, rectal burning or injury, diarrhea, cystitis, and blood in the urine. Hormonal manipulation, which is mainly used to relieve symptoms without curing the prostate cancer, has possible complications including nausea and vomiting, hot flashes, anemia, lethargy, osteoporosis, reduced sexual desire, liver problems, diarrhea, enlarged breasts, and erectile dysfunction, along with the obvious lack of treatment of the disease itself. Chemotherapy, using medications such as mitoxantrone, prednisone, paclitaxel, docetaxel, estramustine, and adriamycin, has possible complications which are numerous and specific to a given chemotherapy drug.
Sufferers of prostate cancer often experience significant lifestyle changes, including disrupted sexual desire or performance on either a temporary or permanent basis; impotence; extensive monitoring for progression of the disease; stress of illness; and urinary incontinence. Thus, there is a continuing need for alternative treatments for prostate cancer and for improved treatments for prostate cancer.
Cyclooxygenase Inhibitors. Cyclooxygenase is an enzyme-protein complex with a variety of biochemical actions. There are at least three primary COX isoenzymes, COX-1, COX-2, and COX-3. COX-1 is a constitutive enzyme, produced at a reasonably consistent level at all times. It plays an important role in, for example, gastrointestinal protection, kidney function, and the aggregation of blood platelets. COX-2 production is not constant; it varies depending on signals from various biochemical catalysts. For example, in the case of arthritis inflammation and pain, COX-2 responds to tissue damage by oxidizing arachidonic acid, creating prostaglandins which in turn produce local inflammation. COX-3 has been identified relatively recently (Chandrasekharan, et al., PNAS U.S.A., 99(21):13926–31 (2002)). In humans, COX-3 mRNA is expressed most abundantly in the cerebral cortex and heart tissues. COX-3 activity is selectively inhibited by analgesic/antipyretic drugs. It has been suggested that inhibition of COX-3 could represent a mechanism by which these drugs decrease pain and possibly fever.
Prostaglandins play a major role in the inflammatory process and the inhibition of prostaglandin production, especially production of PGG2, PGH2, and PGE2, has been a common target of anti-inflammatory drug discovery. However, common non-steroidal anti-inflammatory drugs (hereinafter “NSAIDs”) that are active in reducing the prostaglandin-induced pain and swelling associated with the inflammation process are also active in affecting other prostaglandin-regulated processes not associated with the inflammation process.
NSAIDs have been found to prevent the production of prostaglandins by inhibiting enzymes in the human arachidonic acid/prostaglandin pathway, including the cyclooxygenase enzymes. Traditional non-steroidal anti-inflammatory drugs, such as aspirin, work by inhibiting both COX-1 and COX-2. Thus, non-specific NSAIDs can have a damaging effect on the gastrointestinal tract, kidneys, and liver; blocking COX-1 can make the stomach lining more vulnerable, and reduced thromboxane production thins the blood, making gastrointestinal hemorrhage more likely, and may cause inadequate regulation of cellular immune functions and the secretion of various cytokines. The use of high doses of most common NSAID's can produce severe side effects, including life threatening ulcers, that limit their therapeutic potential.
COX-2 is associated with inflammation and provides a viable target of inhibition which more effectively reduces inflammation and produces fewer and less drastic side effects. Thus, researchers have been motivated to develop selective COX-2 inhibitors to reduce inflammation and relieve pain without the gastrointestinal damage brought on by inhibiting COX-1. In addition, the current scientific understanding in the art suggests that COX-2 inhibition may serve an important function in promoting normal cell growth in the colon, pancreas, breast tissue, and other organ systems.
Some compounds which selectively inhibit cyclooxygenase-2 have been described in U.S. Pat. Nos. 5,380,738, 5,344,991, 5,393,790, 5,434,178, 5,474,995, 5,510,368 and WO documents WO96/06840, WO96/03388, WO96/03387, WO96/25405, WO95/15316, WO94/15932, WO94/27980, WO95/00501, WO94/13635, WO94/20480, and WO94/26731.
Drugs such as valdecoxib, celecoxib, and rofecoxib are intended to selectively inhibit COX-2 with minimal effect on COX-1. However, despite the emphasis on COX-2 inhibition, even these drugs appear to have serious long term side effects, such as the breakdown in digestive protective mucus and prevention of normal healing processes. There is thus a continuing need for more specific and non-specific COX-2 inhibitors which avoid side effects associated with COX-1 inhibition.
Natural COX-2 Inhibitors. Several herbs have been found to inhibit the COX-2 enzyme. For example, holy basil has been found to possess significant anti-inflammatory properties and is capable of blocking both the cyclooxygenase and lipoxygenase pathways of arachidonate metabolism. Ursolic acid and oleanolic acid, two of the recognized phytonutients of holy basil, have been found to have a significant COX-2 inhibitory effect.
Similarly, shogaols and gingerols, pungent components of ginger, have been found to inhibit cyclooxygenase. Eugenol, another active constituent of several medical herbs, has also been found to be a 5-lipoxygenase inhibitor and to possess potent anti-inflammatory and/or anti-rheumatic properties.
Scutellaria baicalensis also has been found to inhibit the COX-2 enzyme. According to the USDA database, green tea contains six constituents having cyclooxygenase-inhibitor activity. According to the Napralert database, green tea contains fifty one constituents having anti-inflammatory activity. The polyphenols in green tea were found to cause a marked reduction in COX-2. Flavan-3-ol derivatives (+)-catechin, also present in green tea, have been reported to be COX-1 and COX-2 inhibitors. In addition, salicylic acid, another constituent of green tea, also has been found to be a COX-2 inhibitor.
Berberine, found in barberry and Chinese goldthread, has also been found to inhibit COX-2 without inhibiting COX-1 activity.
In U.S. Pat. No. 6,387,416, Applicants disclosed the inventive compositions and their use for reducing inflammation. The contents of U.S. Pat. No. 6,387,416 are hereby incorporated by reference in their entirety. Surprisingly, as discussed in greater detail below, it has been determined that the inventive compositions are useful for treating prostate cancer as well.
Use of COX-2 Inhibitors for Treating Cancer. It has been postulated that COX-2 inhibitors may be useful for treating cancer. Yet only a very few patents actually disclose the use of COX-2 inhibitors for treating any cancers. In U.S. Pat. No. 5,466,823 to Talley, et al., (Pyrazol-1-yl)benzene sulfonamides are disclosed as inhibitors of cyclooxygenase-2, and for use in the treatment of inflammation, arthritis, and pain, and as being useful for preventing colon cancer. However, their use for actually treating colon cancer or for treating or preventing other neoplasias is not disclosed.
U.S. Pat. No. 6,469,040 to Seibert, et al., discloses a method of using a specific, disclosed class of cyclooxygenase-2 inhibitor derivatives in preventing and treating epithelial cell neoplasia in a subject.
U.S. Pat. No. 6,534,540 to Kindness, et al., discloses a combination of the proprietary HMG-COA reductase inhibitor lovastatin and the proprietary COX-2 inhibitor rofecoxib for the treatment of cancer, especially prostate cancer, and a method of treatment of cancer, especially prostate cancer, by that combination.
Based on the limited body of art disclosing the use of COX-2 inhibitors for treating any cancer, and the need for effective treatments for prostate cancer in particular, it is apparent that there is a great and immediate need for new COX-2 inhibitors for treating prostate cancer. This need is met by the inventive methods and compositions, which treat prostate neoplasias without significant side effects.